With Lemtrada alemtuzumab possibly set to reach the market next year for multiple sclerosis, Sanofi is seeking to limit its potential long-term costs by purchasing some of the Genzyme Corp. contingent value rights covering the drug.

The pharma last week started a modified Dutch auction tender offer to purchase up to 86.8 million, or 30%, of the outstanding CVRs at $1.50-$1.75. The range is a 7-25% premium to the CVR's close of $1.40 on